Greenwald S.A., Bourdon J.A, Mollet, H.F.
(SAG)(HFM) Monterey Bay Aquarium, 886 Cannery Row, Monterey, CA 93940, USA; (JAB) Nordica Drive, Croton-on-Hudson, NY 10520, USA.

Tooth structure of male and female pelagic stingrays, Dasyatis violacea

Two male (53 and 57 cm disk width) and 4 female pelagic stingrays {iDasyatis violacea} (69 to 83 cm disk width in December 1996) were maintained in a fiberglass tank (5.2 m diameter, 1.07 m water depth) at T = 20 C for a feeding and growth experiment. This represented a well defined and alternative source of dasyatid teeth for study or paleontological comparative purposes. Shed teeth and dermal denticles were collected weekly starting in Jan. 1997 and sorted according to morphological criteria. The objective of the study is the determination of 1) shed rates of teeth and dermal denticles, 2) odontological characteristics which reflect sex and tooth position, 3) possible changes of male teeth during the breeding season. The preliminary analysis based on 121 teeth identified 7 odontological types. The large anterior and antero-lateral teeth are cuspidate in both sexes, but those likely to be female derive this characteristic differently. Ten % of all teeth had a partial or fully developed second cusp, an unexpected morphological feature usually associated with mobulids. We hope this investigation will provide information on sexual and ontogenic heterodonty of the pelagic stingray and help in the identification of fossil stingray teeth.

Keywords: Dasyatis violacea, tooth structure, tooth morphology, dermal denticles, placoid scales, cuspidate, heterodonty, mobulidae, dasyatidae

Abstract for 1997 AES Seattle Poster Session

Added to home page : March. 15, 1997. HFM

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